I'm going to press and pin the barrel. I have one of the virgin Yugo trunnions, which should make it easy.

If I was having to start with a threaded trunnion I'd probably bore it smooth and pin it.

Timing the gas ports on a threaded setup isn't all that bad - just torque the barrel in place a few times to make sure the threads are all mated up, put a witness mark on, and then line up on that - but press and pin is way easier. It's one of the things I expressly like about the AK.

Using a pressed trunnion that already has a pin hole makes things a lot harder. The most reasonable solution for that is to thread the trunnion. wttool.com has the proper tap for $30-ish, which is amazingly cheap, but tapping hard steel like a trunnion can be iffy. If you cut internal threads on the lathe, you might want to press a sacrificial pin in first, bore it flush with the ID, and then thread across is. The threading tool will tend to deflect going across the interruption of the empty pin slot, which can cause troubles, particularly with a light duty lathe like mine.

Hmm... looking at my Yugo trunnion while I'm typing this, I just had another idea. Back in the main AK section I posted some pictures of stamped Valmets; one of them used a rivet instead of a plain barrel pin, since the Valmet's upswept receiver front is missing the place where the lower rivet would go. So they made the barrel pin take the place of the lower rivet.

It looks like there's room to open up the lower-front rivet hole in the Yugo trunnion. You'd have to offset it up a bit. For a garage shop, you could carefully egg the hole up with a carbide burr in a Dremel until it intersects the barrel, then make the hole round with a drill and reamer.

Again, while drilling and reaming, a piece of scrap steel or old barrel stub pressed into the trunnion would help a lot. Ideally the hardness should be the same as the trunnion to keep the bits from wandering, but even softer metal would be better than nothing.

The two Beowulf cartridges I have slide neatly in and out under the feed lips. It really needs a slight notch at the front to keep from snagging the case mouth, but so goes the USGI M-16 mag I have.

I hadn't started making the magwell. Now I guess there's no reason to start.

Crazy thing is, the 5.45 magazine isn't even *close*; it requires grinding all over the place to feed a Beowulf. Stand a 5.45 and a 5.56 side by side, and other than the shoulder distance, there's f-all difference between them.

The bore in my Yugo trunnion is .906, and a 15/16-32 tap has a minor diameter of .907, which is darned near perfect. wttool.com has the tap for $22.

Interesting I have been debating on thread size on the switch barrel build Im pretty sure 1-12 will be fine in a yugo trunion but with the all the voids and hollows of a Rommy I want all the thread engagement I can get. Its not very hard to bore a trunion mine cit really easy. I made a set up guage that chucks into the mill that when it slides up and down in the clamoed in trunion with no interferance its good to bore. I use the same tool to set up for truing the bolt and truing the face.

So you plan to just drill the barel pin hole higher to allow the pin to clear the chamber ???

No joke, I just had this idea yesturday while reading a shotgun news...and now here is! I had an idea for a 12 gauge AR but there it was already made in there too! Great mnds think alike..and like guns!

My build went on the back burner when Beowulf ammunition went away, but I just found out Starline is shipping Beowulf brass again. I need to call Alexander Arms and Impact and check on the status of my orders (which have been back-ordered for a year now), and see if they'll honor the original price. If not, I'll cancel and order directly from Starline.